Sulfuric acid esters of butynediol-polyalkylene oxide condensates as antifoggant in silver halide emulsions

ABSTRACT

A PHOTOGRAPHIC ELEMENT HAVING INCORPORATED IN THE LIGHT-SENSITIVE SILVER HALIDE EMULSION LAYER OR IN A COLLOID LAYER CONTIGUOUS THEREWITH A SULFURIC ACID ESTER OF A CONDENSATION PRODUCT OF AN ALKYLENE OXIDE WITH A BUTYNEDIOL.

United States Patent 3,597,214 SULFURIC ACID ESTERS F BUTYNEDIOL-POLY- ALKYLENE OXIDE CONDENSATES AS ANTI- FOGGANT IN SILVER HALIDE EMULSIONS E Scudder Mackey and Fritz Dersch, Binghamton, N.Y., and Robert E. Leary, Somerville, N..l., assignors to GAF Corporation, New York, N.Y. No Drawing. Filed Jan. 12, 1968, Ser. No. 697,304 Int. Cl. G03c N34 US. Cl. 96-109 8 Claims ABSTRACT OF THE DISCLOSURE A photographic element having incorporated in the light-sensitive silver halide emulsion layer or in a colloid layer contiguous therewith a sulfuric acid ester of a condensation product of an alkylene oxide with a butynediol.

This invention relates to photographic emulsions and, more particularly, to the sensitization of these emulsions by incorporating therein certain sulfuric acid esters of polyoxyalkylene derivatives of butynediols.

Sensitization of silver halide emulsions by the use of polyoxyalkylene or polyalkylene oxides is well known and is described in US. Pats. 2,423,549 and 2,441,389 while the use of various derivatives of polyalkylene oxides as, for example, condensation products of an alkylene oxide with glycols is described in US. Pat. 2,240,472.

A deleterious effect with the use of these materials is their tendency to increase fog which is defined as the loss of sensitivity of the emulsion, during storage, resulting from the spontaneous occurrence of a developable species without exposure to light. Since the intensity of the resulting fog is dependent on both the inherent qualities of the emulsion and on the conditions of subsequent processing, the fog quality becomes dependent, under constant conditions of development, on changes in such storage variables as time, temperature and relative humidity. Fog can also be the result of conditions present in high temperature processing.

Since the addition of sensitizer compounds causes an increase in fog during storage, their use had been somewhat limited especially under the aforesaid conditions of high temperature and humidity storage or under conditions of high temperature processing. This had led to the need for special and somewhat exotic antifoggant compounds for use with these materials (see US. Pats. 2,704,716, 2,716,062 and 2,728,666). In a later development, described in US. 3,255,013, the use of certain polyoxyalkylene derivatives of butynediols was described in which conventional anti-foggants were suitable since these compounds did not cause an excessive increase in fog on storage.

It is an object of this invention therefore, to provide novel sensitizers for silver halide emulsions.

It is a further object of this invention to provide such sensitizers which prevent formation or, at least, minimize fog development on storage and/or subsequent processing under conditions of high temperature.

It is also an object of this invention to provide such sensitizer compounds which reduce the development of surface static charges.

In accordance with this invention it has been found that certain sulfuric acid esters of the aforesaid polyoxyalylene derivatives of a butynediol as hereinafter described either prevent formation of or substantially curtail fog development without any sacrifice of sensitivity. This is especially true where film is subject to storage and/or subsequent processing at high temperature.

Therefore this invention is based at least in part in the discovery that compounds of the sulfuric ester are satisfactory sensitizers for silver halide emulsions which do not cause excessive fog on development.

This invention is also based at least in part on the discovery that the incorporation of these compounds into silver halide emulsions results in increases in film speed (i.e., a marked increase in density for a given exposure) and improvement in the covering power of the developed silver. The covering power is defined as the ratio of the optical density at maximum density to the weight of silver per square decimeter in the developed image layer.

This invention is also :based at least in part on the discovery that the incorporation of these compounds into silver halide emulsions results in a marked reduction in the development of surface static charge.

This invention is also based at least in part on the discovery that the incorporation of these sulfuric acid ester compounds into either the silver halide emulsion or into the anti abrasion surface effectively decreases inter-surface repellency thus enabling the use of much higher coating speeds.

The sulfuric esters employed in photographic emulsions in accordance with this invention are compounds of the general formula:

wherein R is an alkylene group of from 2 to about 4 carbon atoms, R R R and R are members selected from the group consisting of hydrogen and an alkyl group of from 1 to about 5 carbon atoms, X is a member selected from the group consisting of hydrogen and the polyoxyalkylene derivative group said group being a compound having the general formula as set forth next such that the compound can be either a monoor diester of sulfuric acid, or a mixture of the two, and m and n are positive integers such that the molecular weight of the ensuing compound is in excess of 300 and up to 150,000

or more.

The procedure below describes the preparation of a preferred sulfuric acid ester of a polyoxyalkylene derivative of butynediol.

PROCEDURE A Preparation of the sulfuric acid ester of the condensation product of ethylene oxide with l,4-di-isobutyl-1,4- dimethylbutynediol.

Four hundred and sixty-two grams of a condensation product of ethylene oxide and 1,4-di-isobutyl-1,4dimethylbutynediol having a molecular Weight of about 1500 and containing less than 0.1% water (sold under the trademark Surfynol 485) were added to a reaction flask and heated, under agitation, to C. The system was flushed with nitrogen and 58 grams of sulfamic acid were added over a period of 30 minutes. This mixture was heated, under agitation and nitrogen flush, to -120 C. and maintained at that temperature for 3 hours. The flask was then cooled to 80 C., the nitrogen stream was stopped and monoethanolamine was added until the pH was adjusted to above 7. Approximately five grams of the amine were required. The system was then'cooled to 60 C., 115 grams of ethanol SD-3A were added and, after 20 minutes of agitation, grams of water were added. Agitation was continued for 30 minutes to completely dissolve the sulfuric acid ester. Citric acid was added from a 10% aqueous solution to adjust the pH to 6.5-7.5. The

ester content, assayed by the standard Hyamine-rnethyl ene Blue titration procedure, was 63.8% and the molecu lar weight was 1731. Isolation of the ester from the solution was quantitative.

The actual product obtained may be a mixture of esters with varying amounts of non-ionic (i.e., non-esterified material) depending on such factors as the relative proportions of reactants and reaction conditions.

The aforesaid improvements can be realized by incorporating such sulfuric acid esters in the light-sensitive silver halide emulsion itself or in the undercoating, substratum, intermediate coating, overcoating or surface coatmg.

The sulfuric acid esters may also be advantageously employed in various types of photographic silver halide emulsions, e.g., non-sensitized emulsions, orthochromatic, panchromatic and X-ray emulsions. If used with sensitizing dyes, the ester material may be added to the emulsion before or after the dyes are added. Various silver halides may be used as the light-sensitive component, such as silver bromide, silver iodide, silve chloride or mixed silver halides. The sulfate esters may be used in emulsions intended for black and white photography or color photography, e.g., emulsions containing color forming components. For the emulsion for color photography, a developer compound of the primary aromatic amine type as, for example, dimethyl amino aniline should be incorporated with a suitable color forming compound having a group such as hydroxyl or methylene to couple with the oxidizer group of the developer in the emulsion.

The dispersing agent in the photographic emulsion may be gelatin or some other hydrophilic compound, such as collodion, albumen, methyl cellulose, polyvinyl alcohol, polyvinylpyrrolidone or the like.

The quantity of the sulfate ester added to the emulsion will depend to a large extent on the layer into which it is incorporated. In any event, the concentration range, dependent on additive location, is from 0.5 to grams per mole of silver halide.

Several examples are set forth below to illustrate the nature of the invention and the manner of carrying it out. However, the invention should not be considered as being limited to the details thereof.

EXAMPLES l-3 These examples illustrate the efiectiveness of compounds of the type described above in increasing the speed of silver halide emulsions without any resultant increase in fog.

A gelatin-silver halide emulsion in which the silver halide consists of 4% silver iodide and 96% silver bromide was prepared in a conventional manner and brought up to its maximum light sensitivity. It was then readied for coating on film base, that is, melted at 40 C. and neces sary coating finals were added as, for example, sensitizing dyes, antifoggants, surfactants such as saponin and hardeners such as formaldehyde. A 10% aqueous solution of a sulfuric ester of a condensation product of ethylene oxide and 1,4-butynediol having a molecular weight of about 1500 was prepared and 10 cc. of this solution were added to a sample of the above described emulsion, containing about 0.4 mol of silver halide. A sample of the same emulsion, but not containing the sulfuric acid ester, served as control. The so-prepared emulsion samples were coated on a suitable cellulose ester film base and dried. Samples of these film coatings were then exposed in a Type I-B Sensitometer and developed in a developer of the following composition:

Distilled water: 500 ml.

Metol: 2.2 grams Sodium sulfite, anhydrous: 72.0 grams Hydroquinone: 8.8 grams Sodium carbonate, monohydrated: 56.0 grams Potassium bromide: 14.0 grams Water to make 1 liter.

The results are tabulated below.

Sulfuric Fog density acid Density (after 6 days ester, Relative (after 6 even test and grams speed dev.) 6 day.)

EXAMPLES 4-7 Polyethyl- Fog density ene oxide Sulfuric (after 1 day lauryl acid Rela Density at F. and ether, ester, tive (after 6 50% RH and grains grams speed day.) 6' dev.)

Example:

4 0 0 100 0. l8 0. 30 5 l 140 0. 30 0. 50 6 1 2 0. 20 0. 34 7 l 4 150 0. 16 0. 28

EXAMPLES 8-9 These examples illustrate the effectiveness of the sulfuric ester compounds when added to other than the emulsion layer.

A gelatin-silver halide emulsion in which the silver halide consists of 4% silver iodide and 96% silver bromide was prepared in a conventional manner. It was then readied for coating on film base, that is, melted at 40 C. and necessary coating finals were added such as sensitizing dyes, stabilizers and hardeners. The so-prepared emulsion samples were coated on a suitable cellulose ester base and dried. A 2% aqueous gelatin solution containing 10% on weight of dry gelatin) of the sulfuric acid ester described above in Examples l3 was coated on the emulsion side of the film base as an anti-abrasion layer. A sample of the same emulsion coated film base was also coated with an anti-abrasion layer consisting of a 2% aqueous gelatin solution Without the sulfuric acid ester. After drying, the film samples were exposed and processed as described in Examples 1-3 above. The results are tabulated below:

ments made on surface resistivity. Since these measurements are indicative of the static susceptibility of the film surface, they show the beneficial effect of the addition to the anti-abrasion coating of the compounds of this invention.

Static susceptibility (surface resistivityXlO meg.) at

72 F. and 72 F. and 72 F. and Anti-abrasion coating 13% RH 22% RH 40% RH Example 8. 2% gelatin solution plus 180 60 10 0.2% sulfuric ester. 2% gelatin solution 1, 000 1,000 250 EXAMPLES ll Sufrace resis- Additive tivity (meg) Example:

10 Control 15710 11 Sulfuric ester Surfynol 485.. 0.6X10

EXAMPLES 12-13 These examples illustrate the ability of the sulfuric ester additive to decrease surface repellency and thereby permit much higher coating speeds.

A silver halide emulsion in gelatin containing 4% silver iodide and 96% silver bromide was prepared in a conventional manner. It was then readied for coating on a film base as described earlier. An amount of the sulfuric ester of Surfynol 485 equal to 0.5% based on solids content was added to the emulsion as a coating aid. A sample of the same emulsion was mixed with saponin, a conventional coating aid. The so-prepared emulsion samples were coated on a suitable cellulose ester base. These emulsions were then coated with the anti-abrasion layer by a high speed air-knife coating using the wet on wet technique. The results are tabulated below.

Maximum speed before surface While exemplary embodiments of the invention have been described, the true scope of the invention is to be determined from the following claims.

What is claimed is:

1. A photographic element comprising a support and a light-sensitive silver halide emulsion layer having in a layer selected from the group consisting of the emulsion layer and a colloid layer contiguous therewith a sulfuric acid ester of a condensation product of an alkylene oxide having from 2 to 4 carbon atoms with a butynediol, said ester having a molecular weight in excess of 300 and said ester being a compound of the following general formula:

wherein R is an alkylene group of from 2 to about 4 carbon atoms, R R R and R are members selected from the group consisting of hydrogen and an alkyl group of from 1 to about 5 carbon atoms, X is a member selected from the group consisting of hydrogen and the polyoxyalkylene derivative group as set forth in the general formula and m and n are positive integers such that the molecular weight of the ensuing compound is in excess of 300 and up to 150,000.

2. The photographic element as defined in claim 1 wherein the sulfuric ester is a compound having the following formula:

wherein m and n represent integers providing a molecular weight in excess of 1700, and X is a member selected from the group consisting of hydrogen and polyoxyalkylene derivative group as set forth in the formula 3. The photographic element as defined in claim 2 wherein the sulfuric ester is the monoester.

4. The photographic element as defined in claim 2 wherein the sulfuric ester is the diester.

5. The photographic element as defined in claim 2 wherein the sulfuric ester is a mixture of the monoand diesters.

6. The photographic element as defined in claim 1 wherein the sulfuric ester is located in the silver halide emulsion.

7. The photographic element as defined in claim 1 wherein the sulfuric ester is located in the surface coating layer.

8. The photographic element as defined in claim 1 wherein the sulfuric ester product is employed in an amount of from about 0.5 to 10 grams per mole of silver halide.

References Cited UNITED STATES PATENTS 3,039,873 6/1962 Beavers 96-l07X 3,068,102 12/1962 Chiesa 96-107 3,255,013 6/1966 Dersch et a1. 96-107 NORMAN G. TORCHIN, Primary Examiner R. E. FIGHTER, Assistant Examiner U.S. c1. X.R. 96-114.2 

